[Util] add get_topk

src/finn/util/test.py

@@ -77,6 +77,11 @@ def get_test_model_untrained(netname, wbits, abits):
     return get_test_model(netname, wbits, abits, pretrained=False)
 
 
+def get_topk(vec, k):
+    "Return indices of the top-k values in given array vec (treated as 1D)."
+    return np.flip(vec.flatten().argsort())[:k]
+
+
 def soft_verify_topk(invec, idxvec, k):
     """Check that the topK indices provided actually point to the topK largest
     values in the input vector"""